Why young patients with cancer refuse the human papillomavirus vaccine
Authors: Mike Fillon
Journal: CA A Cancer Journal for Clinicians (2023)

Despite their elevated risk for developing cervical, oropharyngeal, and other human papillomavirus (HPV)–related cancers and the strong and consistent evidence for the HPV vaccine’s safety and efficacy, many young cancer survivors reject this vaccine. In a new study appearing in Cancer, researchers from Emory University School of Medicine and the Aflac Cancer & Blood Disorders Center (both in Atlanta, Georgia), the University of Alabama at Birmingham, and St. Jude Children’s Research Hospital (Memphis, Tennessee) investigate the reasons that many young survivors are rejecting this vaccine (doi:10.1002/cncr.34521). Senior study author Wendy Landier, PhD, a professor in the Division of Pediatric Hematology/Oncology and deputy director of the Institute for Cancer Outcomes and Survivorship at the University of Alabama at Birmingham Marnix E. Heersink School of Medicine, says that this is the first study to systematically characterize reasons for HPV vaccine refusal by a large group of young cancer survivors (or their parents). HPV vaccine–naive childhood, adolescent, and young adult cancer survivors were invited to participate in an open-label clinical trial conducted from January 12, 2013, and October 5, 2018, that evaluated the immunogenicity of the vaccine and safety of a quadrivalent HPV vaccine. According to Dr Landier, “We methodically recorded study refusal reasons in real time for those declining participation.” Two researchers independently reviewed these reasons for refusal and developed coding lists for primary and secondary reasons for declining the vaccine. Four of the study researchers then developed the final categories of reasons for refusal. Associations of these various reasons with participant characteristics, including sex, race/ethnicity, cancer diagnosis, and age, were examined to help guide clinicians in improving adherence with vaccine guidelines. Of the 755 survivors eligible to participate in the study of vaccine safety and efficacy, 301 (39.9%) declined to participate. Among those who declined, 86 survivors or their parents (28.6%) cited reasons unrelated to the HPV vaccine. For example, Among young cancer survivors who refused participation in a clinical trial of the quadrivalent human papillomavirus (HPV) vaccine for vaccine-related reasons, the most cited reason was related to health beliefs and family decisional processes. The second most common reason was attributed to the survivor/parent having inaccurate information about the vaccine. Oncologists and primary care clinicians should use evidence-based communication strategies to address barriers to HPV vaccination among young cancer survivors. some said that they simply were not interested or were uncomfortable with taking part in any research study or had concerns about the needle sticks required for study-related blood draws, or they mentioned “logistical concerns.” The 215 survivors or their parents who refused clinical trial participation for vaccine-related reasons became the focus of this study. Approximately 75% (75.3%) were non-Hispanic White, 53.0% were male, and 54.9% had had leukemia or lymphoma. The ages of the survivors ranged from 9.0 to 26.9 years; the median age at which they were first offered study participation was 14.2 years. The survivors had completed cancer therapy 1–5 years (median, 2.8 years) before they were offered the study. Health beliefs and family decisional processes: Sixty-seven study subjects (31.2%; i.e., survivors or their parents) declined for reasons including negativity regarding vaccines in general or specific to the HPV vaccine, religious reasons for declining vaccines, and “within the context of family decision-making.” Dr Landier says, “This highlights the negativity that some survivors/parents have toward vaccines (in general and specific to the HPV vaccine), as well as a common process in which families had already made the decision that the survivor would not receive the HPV vaccine.” Vaccine-related information deficits: A total of 49 subjects (22.8%) described reasons that the researchers attributed to inadequate or inaccurate information. Some said that they did not need the vaccine because they were not sexually active or stated that they “decided to wait until closer to when [the] child becomes sexually active.” Others stated that “the vaccine was beneficial for females but thought that males did not need the vaccine.” External influences: A total of 36 subjects (16.7%) cited health care provider influences (“a lack of a provider recommendation for the vaccine or guidance from a provider to delay or decline the HPV vaccine”) and other external influences, such as this vaccine not being required by the survivor’s school. Safety concerns: Researchers reported that 37 subjects (17.2%) had “heard bad things about side effects” from family, friends, or others, or they opined that the vaccine was “too new and we don’t know enough yet” and that they wanted to see “… more research regarding safety and long-term effects.” Vaccine hesitancy/disinterest: Twenty-six subjects (12.1%) said that they were still deciding whether to receive the vaccine and “… wanted more time to decide, wanted to wait, or simply were not ready to begin the vaccine series.” “This study absolutely breaks new ground,” says Tara Henderson, MD, MPH, director of the Childhood, Adolescent, and Young Adult Cancer Survivors Center and section chief of pediatric cancer and blood diseases at the University of Chicago Department of Pediatrics in Illinois. “While it is known that cancer survivors have an elevated risk of developing HPV-associated cancers as compared to the general population, rates of HPV-vaccination among survivors remains suboptimal. Vaccination can prevent HPV infection and thus reduce rates of HPV-associated malignancy. These findings will enable researchers and clinicians to develop targeted educational and messaging interventions aimed at improving vaccination uptake.” Dr Landier says that findings from this study should provide researchers and clinicians with insights into reasons for HPV vaccine refusal among young cancer survivors. “Many of these refusal reasons are potentially addressable through evidence-based communication strategies that speak to survivor and parental concerns and reduce vaccine information deficits and vaccine hesitancy. “Additionally,” adds Dr Landier, “the clinical trial that collected these data regarding refusal reasons has now provided additional evidence underscoring the safety and immunogenicity of the HPV vaccine in young cancer survivors, a population particularly vulnerable to developing subsequent HPV-related malignancies” (doi:10.1016/%20S2352-4642(21)00278-9). “Because young cancer survivors have concerns about the HPV vaccination and its safety for people like themselves, not merely for people in the general population,” says Dr Henderson, “it is critical to develop educational materials, communication guidelines, and interventions for survivors in order to improve uptake of this vaccination.” She recommends that clinicians refer to the Children’s Oncology Group’s longterm follow-up guidelines at http://www.survivorshipguidelines.org/. Dr Landier notes that health care provider recommendations play a critical role in the uptake of HPV vaccination. “Cancer survivors often prefer [to receive] information regarding vaccination from their oncology providers, but many oncology providers do not routinely discuss HPV vaccination. Understanding common reasons for refusal in this population can help health care professionals feel more prepared to address these concerns directly.”